Frank c



(No Model.)

P. O. HALL. GRINDING MILL.

No. 406,522. Patented July 9, 1889.

1 ""'-"'I Illllllllllllllllliii j mezzzor Maya TIWZ UNITED STATES PATENT OFFICE.

FRANK C. HALL, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO WILLIAM C. STEVENSON, OF SAME PLACE.

GRlNDlNG-MILL.

SPECIFICATION forming part of Letters Patent No. 406,522, dated July 9, 1889.

Application filed November 1, 1883. Serial 110.289,?. (No model.) I

To all whom it may concern:

Be itknown that I, FRANK C. HALL, of Philamaterials, if found desirable.

The invention is particularly useful in the grinding of paint, by reason of the fact that I make provision in one mill for a series of grinding-surfaces, so that the capacity of the" mill is equal to as great a number of single mills as there are grindingsurfaces in my improved mill. By so combining a number of grinding-surfaces I secure compactness and economy of space. Further than this I provide a single hopper, including all the openings leading to the series of grinding-surfaces, by means of which, when itis desired to grind a paint of one colorin all the mills, the material may be poured into the hopper common to all, and it will thus find its way to each grinding-surface. When it is desired, however, to grind different colors at the same time, I provide supplemental hoppers, which are placed removablywithin the openings in the bottom of the outer hopper leading to the independent grinding-surfaces, whereby each grinding-surface may be utilized to grind different colors, the material being fed to each grinding-surface through its own hopper. My mill is thus capable of two different kinds of use, namely: first, the simultaneous grinding of several colors, and, secondly, the grinding of one color upon all of the grinding-surfaces of the mill. The supplemental hoppers are removable, and when removed the mill has a larger capacity for grinding paints of one color, all the grinding-surfaces operating thereon. I have found by practical use that a mill of this form, having multiple grinding-surfaces and a hopper common to all, operates to better advantage than a mill with a single hopper and a single grinding-surface-that is to say, the mill with the multiple grinding-surfaces and the single hopper will perform more Work in a given amount of time than a mill of the same size of the old form. The adhesive nature of the material operated upon by these mills causes grinding-surface.

My invention consists, therefore, of a series of grinding-surfaces having an outer hopper common to a11,'with openings in the bottom of said hopperleading to each grinding-surface and' a removable supplemental hopper for each opening, whereby the surfaces may be used to grind one material with the outer hopper common to all, or to grind different materials by the use of the supplemental hoppers.

In the drawings, Figure l is a front elevation of my improved mill. Fig. 2 is a section through the outer hopper, showing one of the supplemental hoppers in place.

In these figures a hopper A is shown supported upon four posts 13, and this hopper is provided with four openings in its bottom plate 0, which lead to the grinding and crushing surfaces of four grinding-mills which are placed directly beneath the hopper. These mills may be of the form shown in Letters Patent granted to me January 22, 1889, No. 396,559, or of any desired form. Instead of four, two or more may be used. In combining the series of mills in one apparatus I provide for driving them simultaneously through the centrally-located shaft a, which carries upon its lower end a crown-wheel b,which receives motion through a bevel-gear d, fixed to the inner end of the shaft (2, upon which is placed the driving-pulley f, which is in connection by belting with a suitable source of power. are provided with gears which mesh into a central driving-gear on the upper end of the shaft a, so that from this central driving-gear all the mills of the series may be driven. It

The spindles of the grinding-mills 5 the runner, and the movement of the runner cleans it from the material adhering thereto, which falls into the discharge-chute and from thence into a suitable receptacle. I provide for the adjustment of the spindles by seating their lower ends in a bearing-block which is held in a pocket formed in a hanger k, pivoted at one end and connect-ed at the other end to the screw-threaded end of a handwheel Z, which has its bearings in one of the lower cross-braces of the machine. By manipulating this hand-wheel a proper adjust- -ment of the spindle may be secured. It will be understood that each spindle has this adjustment.

It will be seen from an inspection of the drawings, particularly Fig. 2, that each of the series of grinding-surfaces has an independent opening leading thereto,with the outer hopperA common to all the openings, so that when it is desired to grind the same kind of mate r rial in all the mills the said material is simply poured into the hopper A, and thus finds its way to the grinding-surface of each mill. When, however, it is desired to grind difierent kinds of material in each mill, the supplemental hoppers are fitted to the openings leading to the grinding surfaces, and thus each grinding-surface is provided with an independent-hopper.

I claim as my invention 1. In combination with a series of independent grinding-surfaces, an outer hopper with openings in the bottom thereof leading to each grinding-surface, and a supplemental removable hopper for each opening, whereby the grinding-surfaces may be utilized to grind material of one kind or color or materials of different kind or color, substantially as described.

2. In a-grinding-mill, a series of independent grinding-surfaces combined with a. single outer hopper and openings Within said hopper, one leading to each grinding-surface, and operating mechanism for the grinding-surfaces, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FRANK O. HALL.

WVit-nesses:

JOHN H. CRAVEN, THos. A. MoADAMs'. 

